As a life simulator, marriage is a key mechanic and stage of life in and is something that has been expanded upon post-launch through updates and DLC. To get that far, players will need to guide their hopeful Sims through the art of flirting, romance, and wooing, provided that the potential marriage partner in question is not part of the player's household and is an NPC. Otherwise, both sides of the relationship can be orchestrated to get both the Sims exactly where the player wants them to be.
In both and in real life, when people get married they become a part of each other's family. In ' case, the now married partner will join the player's household and move into their home. This will make them playable like everyone else in the household, provided that they were an NPC prior to the marriage and moving in, giving the player control of both sides of the relationship. In doing so, this takes away some of the spontaneity of the relationship, and for some, this gives players too much control over World.
As suggested by Reddit User Fntastk, could maintain spontaneity in a marriage relationship by having the NPC partner remain as an NPC while still in the household. This also applies to Sims who have requested to move in, since this will also make an NPC playable. This way, both partners in the relationship won't be orchestrated by the player, and the new member of the family who married/moved in will still be the same character that they were prior to this stage in the relationship.
If a partner asks to move in, and the Sims says no, it will negatively impact the relationship.
Of course, this fix would be optional,since some players want to be able to orchestrate either side of the relationship, but having the spontaneity and unpredictability of an NPC partner would keep things interesting. It would mean that the player has to navigate their Sim through a relationship after marriage/moving in together, while also giving the player less to manage in their
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